Conventionally, there is a known flow passage structure as a means for producing an interaction by mixing a plurality of fluids. The flow passage structure is used in a reactor for generating a chemical reaction between fluids as an interaction between a plurality of fluids of reacting agents, and thereby obtaining a desired reaction product. Patent Document 1 described below discloses one example in which a flow passage structure is used in a reactor.
Patent Document 1 discloses a reactor in which a flow passage structure having a plurality of flow passageways therein is used. Each of the flow passageways has a first inlet path into which a fluid of a first reacting agent is introduced, a second inlet path into which a fluid of a second reacting agent is introduced, a junction path connected to downstream parts of both the inlet paths for joining and mixing the fluids of the reacting agents flowing through the inlet paths, and a reaction path connected to a downstream part of the junction path for circulating a fluid made by joining the fluids in the junction path while reacting the reacting agents contained in the fluid. The first inlet path, the second inlet path, the junction path, and the reaction path in the flow passageway are arranged on one straight line.
The flow passage structure includes an intermediate substrate, a front substrate bonded to a front surface of the intermediate substrate, and a back substrate bonded to a back surface of the intermediate substrate. The plurality of passageways is arranged side by side in parallel to each other in the planar direction of the intermediate substrate. Front surface side groove portions extending linearly are formed on the front surface of the intermediate substrate. Back surface side groove portions are formed at positions on the back surface of the intermediate substrate, the positions corresponding to the front surface side groove portions, in parallel to the front surface side groove portions. Through holes penetrating the intermediate substrate in the thickness direction and being connected to terminal points of the back surface side groove portions are formed at positions on the intermediate substrate in the middle of the longitudinal direction of the front surface side groove portions. The first inlet paths and the reaction paths are formed by sealing openings of the front surface side groove portions formed on the front surface of the intermediate substrate with the front substrate. The second inlet paths are formed by sealing openings of the back surface side groove portions formed on the back surface of the intermediate substrate with the back substrate. The junction paths are formed by sealing one-side openings of the through holes formed on the front surface of the intermediate substrate with the front substrate and sealing the other-side openings of the through holes formed on the back surface of the intermediate substrate with the back substrate.
In the above reactor, the first inlet paths and the second inlet paths are arranged side by side in the thickness direction of the intermediate substrate forming the flow passage structure, and both the inlet paths are joined together in the thickness direction of the intermediate substrate. Thus, in comparison to a configuration that first inlet paths and second inlet paths are formed on the same surface of an intermediate substrate and both the inlet paths are joined together on the surface, the plurality of flow passageways can be more closely arranged in the planar direction of the intermediate substrate. As a result, even with the flow passage structure of the same size, more flow passageways can be provided in the flow passage structure. Therefore, in the above reactor, a treatment amount (reaction amount) of the fluids can be increased without increasing the size of the flow passage structure.
However, in the above configuration, when the fluid of the first reacting agent and the fluid of the second reacting agent are joined in the junction paths and then flow through the reaction paths, a reaction between the fluids is not easily facilitated. A reason thereof is as follows.
The reaction between both the fluids in the reaction paths is generated on a contact interface between the fluids. Thus, the more an area of the contact interface is increased, the more the reaction between the fluids is facilitated. However, in the above configuration, after an agitation state of the fluids following joining of the fluid of the first reacting agent and the fluid of the second reacting agent in the junction paths is settled down in the reaction paths, the area of the contact interface between both the fluids becomes substantially constant. Therefore, only a fixed amount of reactions in accordance with the area of the contact interface is generated.